Benzene drying columns or towers are commonly employed to purify benzene for use in processes such as the alkylation of benzene to ethylbenzene (EB). In some cases, the benzene supply contains chloride salts and organic chlorine compounds. The chloride salts hydrolyze in the direct fired heater or reboiler of the tower in the presence of water. The organo chlorine compounds can undergo nucleophilic substitution, in the presence of water, to form an alcohol and HCl. The HCl and water then travel to the overhead due to their boiling points. If untreated, the overhead lines from such benzene columns or towers are highly corrosive resulting in damage to the overhead conduits, and to condensers, heat exchangers, pumps, accumulators and the like that are in fluid communication with such conduits.
Typically, corrosion inhibitors that may be employed are amines or amine based to neutralize the corrosive acidic species. The amine based filming corrosion inhibitors form a protective barrier on the metal surfaces of the tower and ancillary equipment. Unfortunately, these nitrogen containing products poison zeolite catalysts that are often employed in the benzene alkylation processes. The present invention is directed toward the provision of effective corrosion inhibition with a non-nitrogen containing inhibitor that will not adversely affect zeolite catalysts functioning in downstream processes such as the alkylation of benzene with ethylene to form EB. The production of EB is commercially important as it is a precursor for styrene monomer.